Concern over the leakage of gasoline into water supplies has increased in recent years. At gasoline service stations there is the potential problem of a gasoline leak from the tank housing the gasoline. If a leak should occur, gasoline could enter and contaminate the water supply.
Because of the serious consequences associated with gasoline contaminated water, it would be very beneficial to be able to detect if such contamination occurred. In one known commercially available apparatus for sensing the presence of hydrocarbons, nitrogen under pressure is utilized. This nitrogen is located in a pressurized tube. When the pressurized tube is perforated because of the presence of hydrocarbons, a drop in pressure is sensed indicating that hydrocarbons are present. However, such an apparatus is relatively expensive and requires that the pressure be maintained, which pressure could be accidently lost by an unexpected perforation during handling, for example.
Another known device for detecting hydrocarbons utilizes a sequenced styrene-butadiene copolymer strip which is connected at one end to the device to place a spring under tension. This hydrocarbon strip deterition triggers an indication of the presence of hydrocarbons. This device is not connected to a well casing nor does it show the ability to provide hydrocarbon detection at different locations along a relatively great length because the hydrocarbon detecting strip is typically 20-25 centimeters long.
To overcome the deficiencies of the prior art, the present invention is directed primarily to detecting the presence of gasoline in a fully perforated well casing installed in the ground. In that regard, the sensing element of the present invention is a rod or filament which is capable of supporting a weight and having a maximum length of tens of feet.